/*
 * Copyright 2015 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "src/gpu/ganesh/ops/GrMeshDrawOp.h"

#include "src/gpu/ganesh/GrOpFlushState.h"
#include "src/gpu/ganesh/GrOpsRenderPass.h"
#include "src/gpu/ganesh/GrRecordingContextPriv.h"
#include "src/gpu/ganesh/GrResourceProvider.h"

GrMeshDrawOp::GrMeshDrawOp(uint32_t classID) : INHERITED(classID) {}

void GrMeshDrawOp::onPrepare(GrOpFlushState *state)
{
    this->onPrepareDraws(state);
}

void GrMeshDrawOp::createProgramInfo(GrMeshDrawTarget *target)
{
    this->createProgramInfo(&target->caps(), target->allocator(), target->writeView(), target->usesMSAASurface(),
        target->detachAppliedClip(), target->dstProxyView(), target->renderPassBarriers(), target->colorLoadOp());
}

bool GrMeshDrawOp::CombinedQuadCountWillOverflow(GrAAType aaType, bool willBeUpgradedToAA, int combinedQuadCount)
{
    bool willBeAA = (aaType == GrAAType::kCoverage) || willBeUpgradedToAA;

    return combinedQuadCount >
        (willBeAA ? GrResourceProvider::MaxNumAAQuads() : GrResourceProvider::MaxNumNonAAQuads());
}

// This onPrepareDraws implementation assumes the derived Op only has a single programInfo -
// which is the majority of the cases.
void GrMeshDrawOp::onPrePrepareDraws(GrRecordingContext *context, const GrSurfaceProxyView &writeView,
    GrAppliedClip *clip, const GrDstProxyView &dstProxyView, GrXferBarrierFlags renderPassXferBarriers,
    GrLoadOp colorLoadOp)
{
    SkArenaAlloc *arena = context->priv().recordTimeAllocator();

    // http://skbug.com/12201 -- DDL does not yet support DMSAA.
    bool usesMSAASurface = writeView.asRenderTargetProxy()->numSamples() > 1;

    // This is equivalent to a GrOpFlushState::detachAppliedClip
    GrAppliedClip appliedClip = clip ? std::move(*clip) : GrAppliedClip::Disabled();

    this->createProgramInfo(context->priv().caps(), arena, writeView, usesMSAASurface, std::move(appliedClip),
        dstProxyView, renderPassXferBarriers, colorLoadOp);

    // TODO: at this point we've created both the program info and desc in the recording context's
    // arena. In the DDL case, it would be cool if 'recordProgramInfo' could return the
    // pre-existing versions if the program has already been seen. We could then return the
    // memory for the current copy to the arena.
    context->priv().recordProgramInfo(this->programInfo());
}

// ////////////////////////////////////////////////////////////////////////////

GrMeshDrawOp::PatternHelper::PatternHelper(GrMeshDrawTarget *target, GrPrimitiveType primitiveType, size_t vertexStride,
    sk_sp<const GrBuffer> indexBuffer, int verticesPerRepetition, int indicesPerRepetition, int repeatCount,
    int maxRepetitions)
{
    this->init(target, primitiveType, vertexStride, std::move(indexBuffer), verticesPerRepetition, indicesPerRepetition,
        repeatCount, maxRepetitions);
}

void GrMeshDrawOp::PatternHelper::init(GrMeshDrawTarget *target, GrPrimitiveType primitiveType, size_t vertexStride,
    sk_sp<const GrBuffer> indexBuffer, int verticesPerRepetition, int indicesPerRepetition, int repeatCount,
    int maxRepetitions)
{
    SkASSERT(target);
    if (!indexBuffer) {
        return;
    }
    sk_sp<const GrBuffer> vertexBuffer;
    int firstVertex;
    int vertexCount = verticesPerRepetition * repeatCount;
    fVertices = target->makeVertexSpace(vertexStride, vertexCount, &vertexBuffer, &firstVertex);
    if (!fVertices) {
        SkDebugf("Vertices could not be allocated for patterned rendering.");
        return;
    }
    SkASSERT(vertexBuffer);
    fMesh = target->allocMesh();
    fPrimitiveType = primitiveType;

    SkASSERT(maxRepetitions == static_cast<int>(indexBuffer->size() / (sizeof(uint16_t) * indicesPerRepetition)));
    fMesh->setIndexedPatterned(std::move(indexBuffer), indicesPerRepetition, repeatCount, maxRepetitions,
        std::move(vertexBuffer), verticesPerRepetition, firstVertex);
}

void GrMeshDrawOp::PatternHelper::recordDraw(GrMeshDrawTarget *target, const GrGeometryProcessor *gp) const
{
    target->recordDraw(gp, fMesh, 1, fPrimitiveType);
}

void GrMeshDrawOp::PatternHelper::recordDraw(GrMeshDrawTarget *target, const GrGeometryProcessor *gp,
    const GrSurfaceProxy * const primProcProxies[]) const
{
    target->recordDraw(gp, fMesh, 1, primProcProxies, fPrimitiveType);
}

// ////////////////////////////////////////////////////////////////////////////

GrMeshDrawOp::QuadHelper::QuadHelper(GrMeshDrawTarget *target, size_t vertexStride, int quadsToDraw)
{
    sk_sp<const GrGpuBuffer> indexBuffer = target->resourceProvider()->refNonAAQuadIndexBuffer();
    if (!indexBuffer) {
        SkDebugf("Could not get quad index buffer.");
        return;
    }
    this->init(target, GrPrimitiveType::kTriangles, vertexStride, std::move(indexBuffer),
        GrResourceProvider::NumVertsPerNonAAQuad(), GrResourceProvider::NumIndicesPerNonAAQuad(), quadsToDraw,
        GrResourceProvider::MaxNumNonAAQuads());
}
